rails.rb

# Avec Rails on écrirait : 
  def create
    @product = Product.create({name => 'A Foo Bar', price => 19.99, description => 'Lorem ipsum dolor'})
  end

# ou plutôt (pour gérer les validations et redirections, non gérées dans l'exemple Symfony)

  def create
    @product = Product.new({name => 'A Foo Bar', price => 19.99, description => 'Lorem ipsum dolor'})
    if @product.save
      redirect_to @product
    else
      render :action => "new"
    end
  end

symfony.php

// src/Acme/StoreBundle/Controller/DefaultController.php
use Acme\StoreBundle\Entity\Product;
use Symfony\Component\HttpFoundation\Response;
// ...

public function createAction()
{
    $product = new Product();
    $product->setName('A Foo Bar');
    $product->setPrice('19.99');
    $product->setDescription('Lorem ipsum dolor');

    $em = $this->getDoctrine()->getEntityManager();
    $em->persist($product);
    $em->flush();

    return new Response('Created product id '.$product->getId());
}